Evening primrose oil is obtained from the seeds of a common wildflower of the evening primrose family native to eastern North America and widely naturalized in Europe and western North America. Most of the seed for oil production is grown commercially.
Native Americans gathered the seeds for food in Utah and Nevada. Those in eastern North America used the whole plant as a poultice for bruises, a tea to treat obesity, and a decoction of the root to treat hemorrhoids. Early settlers used the leaves to treat wounds and to soothe sore throats and upset stomach. Use of the seed oil is relatively recent.
Evening primrose oil has been used as a dietary supplement to provide essential fatty acids, especially gammalinolenic acid (GLA). GLA is an intermediate compound between the essential fatty acid, cis-linoleic acid and prostaglandin production in the body. Factors such as aging, alcohol abuse, cancerous conditions, poor dietary habits, or improper nutrition may prevent the natural conversion of cis-linoleic acid into prostaglandin El. Dietary supplementation of GLA from evening primrose oil can help resolve problems associated with essential-fatty-acid deficiencies.
More than 120 studies in fifteen countries report potential use of the seed oil in treating imbalances and abnormalities of essential fatty acids, including allergy-induced eczema, asthma, migraine, inflammations, premenstrual syndrome (PMS), diabetes, arthritis, and alcoholism. Conflicting results point to the need for further well-designed scientific studies. For example, in some double-blind placebo-controlled clinical studies evening primrose oil significantly reduced breast pain and tenderness, irritability, and mood swings associated with PMS. Another clinical study, however, showed improvement in PMS symptoms from evening primrose oil, but when compared to placebo, the results were deemed statistically insignificant.
Evening primrose oil is available in 500-mg capsules.
No known contraindications or drug interactions have been reported for evening primrose oil. In clinical studies, fewer than 2 percent of patients taking it for long periods reported side effects such as abdominal discomfort, nausea, and headache.
Essential fatty acids deficiency